Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets", "python using java slippers"
"hoc dan luan snippets" » "hoc doanh luan snippets", "hoc dung luan snippets", "hoc tang luan snippets", "hoc dan luan slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("hoc dan luan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hoc dan luan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hoc dan luan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hoc dan luan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.